Small clippy improvements

src/main.rs

@@ -49,6 +49,6 @@ pub fn read_file<P: AsRef<Path>>(rom_path: P) -> Result<Box<[u8]>, io::Error> {
 
 pub fn write_file<P: AsRef<Path>>(path: P, data: &Box<[u8]>) -> Result<(), io::Error> {
     let mut file = fs::File::create(path)?;
-    file.write(&data)?;
+    file.write_all(&data)?;
     Ok(())
 }

src/mbc/mbc2.rs

@@ -61,7 +61,7 @@ impl MBC for MBC2 {
                 }
             }
             0x2000..=0x3FFF => {
-                if addr & 0x0100 == 1 {
+                if addr & 0x0100 == 0 {
                     self.rom_bank_no = val & 0x0F;
                     println!("MBC2: Selecting bank {:02X}", self.rom_bank_no);
                 } else {

src/sound/mod.rs

@@ -5,7 +5,7 @@ mod square;
 mod wave;
 
 use self::pulse_simple::Playback;
-use std::sync::{Arc, Mutex};
+use std::sync::{Arc, Mutex, atomic::{AtomicBool, Ordering}};
 use std::thread;
 
 const OUTPUT_SAMPLE_RATE: usize = 48100;
@@ -332,12 +332,12 @@ pub struct Sound {
 pub struct SoundManager {
     pub sound_object: Arc<Mutex<Sound>>,
     handle: Option<std::thread::JoinHandle<()>>,
-    do_exit: Arc<Mutex<bool>>,
+    do_exit: Arc<AtomicBool>,
 }
 
 impl Drop for SoundManager {
     fn drop(&mut self) {
-        *self.do_exit.lock().unwrap() = true;
+        self.do_exit.store(true, Ordering::Relaxed);
         self.handle.take().and_then(|h| h.join().ok());
     }
 }
@@ -347,7 +347,7 @@ impl SoundManager {
         let mut res = SoundManager {
             sound_object: Arc::new(Mutex::new(Sound::new())),
             handle: None,
-            do_exit: Arc::new(Mutex::new(false)),
+            do_exit: Arc::new(AtomicBool::new(false)),
         };
 
         res.launch_thread();
@@ -371,7 +371,7 @@ impl SoundManager {
                     // Counter, used for calling the 512 Hz timer
                     let mut counter = 0;
 
-                    while !*do_exit.lock().unwrap() {
+                    while !do_exit.load(Ordering::Relaxed) {
                         for _ in 0..100 {
                             let (s1, s2) = {
                                 let mut c_obj = obj.lock().unwrap();